WO1989002177A1

WO1989002177A1 - Current connection member for large amperages, especially to be used in metal-enclosed electric systems

Info

Publication number: WO1989002177A1
Application number: PCT/DK1988/000136
Authority: WO
Inventors: Jørgen LØGSTRUP
Original assignee: A/S Løgstrup Steel, Kvistgård
Priority date: 1987-09-04
Filing date: 1988-08-18
Publication date: 1989-03-09
Also published as: EP0382748A1; JPH03501437A; US5055059A; DK463487A; AU2427488A; DK463487D0

Abstract

A power connector element (1) for establishing of electrical connection between a busway and an outgoing or incoming electrical cable (3), generally via a multiphase coupler (8), consists of a unit (1) configured as one piece comprising a number of parallel, massive conductors disposed at a distance from one another and having connection parts at both ends, said conductors being moulded into a common electrically-insulating moulding body, so that only the connection parts are outside. The connection parts are disposed in two areas which are separated by a flange (12) in the moulding body.

Description

CURRENT CONNECTION MEMBER FOR LARGE AMPERAGES, ESPECIALLY TO BE USED N METAL-ENCLOSED ELECTRIC SYSTEMS.

The invention relates to a power connector element for high current intensities, and of the kind dis¬ closed in the preamble to claim 1.

Metal-enclosed electrical coupling systems are at present used to a very wide extent, particularly con¬ figured as module systems with, for example, module dimensions of 190 mm, but other module dimensions are also used. The electrical conductors, insulators.and mounting plates or shelves, on which the many differ- ent electrical components are mounted, e.g. transfor¬ mers, measuring equipment, couplers, relays, fuses, control circuits etc., are contained within the metal -enclosed system, well-protected against dirt, moist¬ ure and contact from the outside. Such metal-enclosed systems are used for the supply of current or power and for the control of electrical units and installa¬ tions of almost every kind. Inside the metal-enclosed systems, solid copper busbars are normally used as con¬ ductors for electrical current or power, and as ex- plained, e.g. in the applicant's earlier Danish pat¬ ents no. 147,588, no. 147,589 and no. 147,590. Out¬ side the metal-_^enclosed systems, more or less flex¬ ible cables are normally used as conductors for el¬ ectrical current or power. V.⁷hen current or power is to be fed into or out of a metal-enclosed system, e.g. for an electrical machine or an installation, an electrical coupling must be effected between one or more cables and parts in the metal-enclosed system. When high currents or high power are involved, there

SUBSTITUTE SHEET are relatively narrow limits for how flexible the cables are, and there are also narrow tolerances with regards to how much and how sharply such cables are able to be bent. Sharp bends in the cable can deform^' the conductors and the insulation, thus reducing the characteristics of the cable.

The object of the invention is to present a current connector element with which it is possible to estab- lish an electrical connection between the individual conductors of a heavy cable and the coupling parts and the like in an electrical system, especially in a metal-enclosed system.

This is achieved by using a current connector element which is configured as disclosed and characterized in claim 1. The conductor element achieved hereby is firm and solid, and is provided at both ends with current connector portions so that the individual cable conductors can be coupled to the one side of the current connector element, and where the other side can be coupled to the fixed parts, e.g. a main switch mounted in the electrical system, and this be¬ ing effected in such a way that the cable is fed in a direct and substantially unbent manner up into one part of the system, while the coupling, e.g.. to the main switch, takes place in another part of the sys¬ tem, the reason being that the current connector ele¬ ment according to the invention is at the sametime here- with arranged to constitute an insulating wall lead- in. The special configuration of the current connec¬ tor element according to the invention has the res¬ ult that the conductors herein are overall insulated from each other and from the surroundings, and that there is access to the conductors only at the con¬ nection areas.

When the current connector element according to the invention is configured as characterized in claim 2, a very solid construction with great mechanical strength is achieved, where a lead-in, e.g. through a sheet metal wall in a metal-enclosed system, is ef¬ fected under completely secure electrical insulation, while at the same time.the lead-in opening in the sheet metal wall is closed. The current connector el¬ ement's two areas with connecting parts can be recti¬ linear portions which, for example, form an angle to each other, whereby a better fitting, an easier ass- embly and a better utilization of space is achieved.

When the current connector element according to the invention is configured as characterized in claim 3, a complete closing of the lead-in opening is achiev- ed, which means that no further means have to be taken into use, regardless of the extent of the de¬ mands placed on the closing of the lead-in opening.

When the current connector element according to the invention is configured as characterized in claim 4, the result is that it can be mounted directly on a coupler, e.g. a switch for current or power to a con¬ sumer, e.g. a machine. The mounting of both the cable and the current connector element can be carried out with solid clamping bolts, so that an effective elec¬ trical connection is always achieved.

When the current connector element according to the invention is configured as characterized in claim 5, a particularly simple manner of connection is ach¬ ieved, so that the connector element is suitable for a number of known couplers, switches etc.

When the current connector element according to the invention is configured as characterized in claim 6, an increased security against outside contact is ach¬ ieved, and thus an increased security against person¬ al injuries and short-circuits. If the part which is provided with further insulation housing is that por¬ tion where the cable is connected, which is generally effected in a separate cabinet, the cabinet can be opened and inspected without any risk of touching of uninsulated parts.

If the current connector element according to the in¬ vention is further configured as characterized in claim 7 , a modular construction of the insulating housing is achieved, thus enabling the free-laying of one cable at a time, for example in the event of repairs to or changes in the system.

When the current connector element according to the invention is configured as characterized in claim 8, further security is achieved against touching and/or short-circuits, in that repair work, assembly or the like can simply not be embarked upon without the cur¬ rent being disconnected.

Finally, if the current connector element according to the invention is configured as characterized in claim 9, one is able to ensure that it is completely impossible to open the insulating housing(s) unless the current is switched off, in that the current is disconnected automatically when access is gained to that area in the system in which the locking arrange¬ ment is disposed. Of course, the locking element can be arranged in such a way that current simply cannot be connected if the locking element is not correctly locked.

The invention will now be described in more detail with reference to the drawing, which shows an embodi- ment of the invention in connection with the supply of electrical power from a metal-enclosed electrical system via a power cable to a consumer, e.g. a machine.

Fig. 1 shows in sketch form a part of a metal-en¬ closed electrical system with a current con¬ nector element according to the invention,

fig. 2 shows a part of fig. 1, and with extra insu- lation of the current connector element,

fig. 3 shows a current connector element according to the invention,

fig. 4 shows the same as in fig. 3, but partly in section, and

fig. 5 shows a plane vertical section in the direc¬ tion V-V in fig. 3.

In fig. 1 is seen a metal-enclosed system 2 or part of such a system comprising two vertical cabinets or cabinet sections. In the right-hand cabinet is seen a heavy power cable 3 with four conductors 4, 3-phases plus 0 or earth, which leads 3-phase power to a not -shown machine or the like.

The cable-shoe terminations on the conductors 4 are electrically connected to the one side of a current connector element 1 by means of solid bolts 19. The other side of the current connector element 1 sits in the left-hand cabinet through an opening in the in¬ termediate wall 9, and this part is electrically con- nected, similarly with bolts 19, to a multi-phase switch 8, said switch 8 being manoeuvred via mechan¬ ical links 6, 7 from the outside of the cabinet door 5 by a not-shown operating handle. Mechanical connec¬ tion between the coupling links 6 and 7 can be estab- lished only when the door 5 is closed. The door's locking element is arranged in such a way that the door cannot be opened unless the switch 8 is off, i.e. when there is no current applied to the current connector element and the cable 3 connected thereto.

In fig. 2 the current connector element is seen on a larger scale, and in figs. 3-5 on an even larger scale. The current connector element 1 comprises (see figs. 3-5) a number of parallel, composite copper conductors 15 having connection portions 13, 14 formed as an integral part hereof, each with holes 18 for assembly bolts 19. All of the conductors are disposed parallel with and at a distance from each other, after which they are moulded into an insulating moulding material 16, e.g. a 2-component resin material. The two parts or areas 10 and 11 are separated by a flange 12 extending around the moulding, and the moulding is further provided with grooves or tracks 17 for the housings for extra insulation as will be discussed later. In the drawing, the areas 10 and 11 are shown rectilinear, but forming an angle with each other. It will be obvious to those familiar with the art that these areas can be configured in any form and at any angle to each other, depending on the ac¬ tual application. During construction, the connec¬ tion portions 13 in area 10, all of which turn to¬ wards the same side, become staggered, and the con¬ nection portions 14 in the area 11 are shown in an embodiment with oppositely directed connection parts. Naturally, the more detailed configuration of the conductors 13, 14 and 15 will depend on how the in¬ dividual parts of the metal-enclosed system are ar¬ ranged, and to which parts the current connector el- ement is to be coupled. It will be obvious to those familiar with the art that innumerable different con¬ ductor configurations are possible without deviating from the basic idea.

In fig. 2 it will be seen that the conductors are connected via bolts 19 to the connection parts 14 of the current conductor element 1 , and thereafter sur¬ rounded by an insulating housing 20, or several hous¬ ings 20, namely a housing or a housing part for each ^' conductor. These housing parts are guided and held in place by the grooves 17 in the current connector el¬ ement. The housings or the housing parts 20 are made of impact-proof plastic, preferably transparent plas- . tic so that an inspection is possible without open- ing the housings or the housing parts. The housings or housing parts 20 are secured in a non-removable manner by a pliant belt 21 , the one end of which is firmly secured to, for example, the intermediate wall 9, and the other end of which is led through an open- ing in the intermediate wall 9 and secured with a locking element 22 which is disposed in an adjacent cabinet, i.e. in the cabinet which also contains the switch 8. The locking element 22 is preferably de- signed in such a way that the current cannot be con¬ nected to the cable, i.e. the switch 8 cannot be op¬ erated, before the locking element 22 is locked cor¬ rectly and the pliant belt 21 is hereby solidly and firmly secured around the protection housings 20. It will be obvious to those familiar with the art that the electrically insulating housings 20 and the belt 21 , which are preferably made of an electrically in¬ sulating material, can be configured, disposed, fast¬ ened and secured in many different ways, without de- viating from the spirit of the invention.

Claims

C L A I M S

1. Power connector element for high current inten¬ sities and for establishing of electrical connection between a busway and an outgoing or incoming electri¬ cal cable (3), c h a r a c t e r i z e d in that it consists of a one-piece unit (1) comprising a number of busbar pieces (15) positioned in a parallel manner but at a distance from one another and having connec- tion parts (13, 14) at both ends, said busbar pieces being moulded into a common, electrically-insulating body (16), so that only the connection parts (13, 14) are outside, and where a flange (12) may be provided in the moulding between the connection parts.

2. Power connector element according to claim 1 , c h a r a c t e r T z e d in that it comprises two areas (10, 11), where all of the connection parts (13) for one end of the busbar pieces (15) are dis- posed in the one area (10) , and where all of the con¬ nection parts (14) for the other end of the busbar pieces (15) are disposed in the other area (11), and in that the connection parts (13, 14) are configured as one piece with the busbar pieces (15), and that the flange (12) is disposed between the two areas (10, 11), thus separating said two areas.

3. Power connector element according to claim 1 or

2, c h a r a c t e r i z e d in that the flange (12) extends around and is substantially plane and at right-angles to the busbar pieces (15).

4. Power connector element according to claim 2 or

3, c h a r a c t e r i z e d in that the connection parts (13, 14) are substantially at right-angles to the busbar pieces (15) , that the busbar pieces are each composed of a number of conductor parts and that the connection parts are provided with holes (18) for clamping bolts (19).

5. Power connector element according to claim 4, c h a r a c t e r i z e d in that all of the con¬ nection parts (13) in one of the areas (10) are led out to the same side (fig. 3).

6. Power connector element according to any of the claims 2-5, c h a r a c t e r i z e d in that it further comprises an electrically-insulating housing (20) which surrounds the whole of the one of the two areas (11).

7. Power connector element according to claim 6, c h a r a c t e r i z e d in that the insulating housing is divided into a number of housings or hous¬ ing parts (20) , one part for each conductor (4) , and arranged to engage with tracks or grooves (17) in the moulding body (16).

8. Power connector element according to claim 6 or 7, c h a r a c t e r i z e d in that the insulating housing or all of the housing parts (20) are surroun¬ ded and secured by a retaining element (21) , which is arranged in such a manner that it cannot be released when the current is connected to the conductors in the housing or in the housing parts.

9. Power connector element according to claim 8, c h a r a c t e r i z e d in that the retaining ele- ment is a pliant belt (21), preferably of electric¬ ally-insulating material, and is secured in a non-re- leasable manner via a locking system (22) disposed in an area which is accessible only when the current is disconnected.